Friction Loss Velocity Table (Schedule 40 pipe)

For steam system to work properly, it is important to maintain reasonable velocities of liquid passing through piping. Pipe velocities are a function of gallons per minute and pipe diameter. Pipe diameters are selected to achieve a velocity of 5-10 feet per second.

Guidelines for using tables:

1. Select value of pump flow (GPM) that is equal to or greater than the pump flow of your application.
2. Velocity is a function of the cross-sectional flow area. Therefore it is constant for a given flow rate and independent of pipe length.
3. Values may vary slightly from other published data due to rounding.
4. Schedule refers to strength of pipe. Wall thickness of pipe varies based on dimensions of pipe as defined in ASME standard 36.10.

Applies to 100 feet of pipe with 60°F water
Showing Schedule 40...	Click to View Schedule 80
Nominal Size 0.5" 0.75" 1" 1.25" 1.5" 2" 2.5" 3" 4" 5" 6" Nominal Size Pipe OD 0.840 1.050 1.315 1.660 1.900 2.375 2.875 3.500 4.500 5.563 6.625 Pipe OD Pipe ID 0.622 0.824 1.049 1.380 1.610 2.067 2.469 3.068 4.026 5.047 6.065 Pipe ID Wall thickness 0.109 0.113 0.133 0.140 0.145 0.154 0.203 0.216 0.237 0.258 0.280 Wall thickness Q V Friction V Friction V Friction V Friction V Friction V Friction V Friction V Friction V Friction V Friction V Friction Q Flow Velocity Loss Velocity Loss Velocity Loss Velocity Loss Velocity Loss Velocity Loss Velocity Loss Velocity Loss Velocity Loss Velocity Loss Velocity Loss Flow GPM FPS PSI FPS PSI FPS PSI FPS PSI FPS PSI FPS PSI FPS PSI FPS PSI FPS PSI FPS PSI FPS PSI GPM 1 1.05 0.91 0.60 0.23 0.37 0.07 0.21 0.02 0.16 0.01                         1 2 2.11 3.28 1.20 0.83 0.74 0.26 0.43 0.07 0.31 0.03 0.19 0.01                     2 3 3.16 6.95 1.80 1.77 1.11 0.55 0.64 0.14 0.47 0.07 0.29 0.02                     3 4 4.22 11.84 2.40 3.01 1.48 0.93 0.86 0.25 0.63 0.12 0.38 0.03 0.27 0.01                 4 5 5.27 17.90 3.00 4.56 1.85 1.41 1.07 0.37 0.79 0.18 0.48 0.05 0.33 0.02                 5 6 6.33 25.09 3.61 6.39 2.22 1.97 1.29 0.52 0.94 0.25 0.57 0.07 0.40 0.03 0.26 0.01             6 7 7.38 33.38 4.21 8.50 2.60 2.62 1.50 0.69 1.10 0.33 0.67 0.10 0.47 0.04 0.30 0.01             7 8 8.44 42.75 4.81 10.88 2.97 3.36 1.71 0.88 1.26 0.42 0.76 0.12 0.54 0.05 0.35 0.02             8 9 9.49 53.17 5.41 13.53 3.34 4.18 1.93 1.10 1.42 0.52 0.86 0.15 0.60 0.06 0.39 0.02             9 10 10.55 64.62 6.01 16.45 3.71 5.08 2.14 1.34 1.57 0.63 0.95 0.19 0.67 0.08 0.43 0.03             10 11 11.60 77.10 6.61 19.62 4.08 6.06 2.36 1.60 1.73 0.75 1.05 0.22 0.74 0.09 0.48 0.03             11 12 12.65 90.58 7.21 23.05 4.45 7.12 2.57 1.87 1.89 0.89 1.15 0.26 0.80 0.11 0.52 0.04             12 13 13.71 105.05 7.81 26.74 4.82 8.26 2.79 2.17 2.05 1.03 1.24 0.30 0.87 0.13 0.56 0.04 0.33 0.01         13 14 14.76 120.51 8.41 30.67 5.19 9.47 3.00 2.49 2.20 1.18 1.34 0.35 0.94 0.15 0.61 0.05 0.35 0.01         14 15 15.82 136.93 9.01 34.85 5.56 10.76 3.21 2.83 2.36 1.34 1.43 0.40 1.00 0.17 0.65 0.06 0.38 0.02         15 16     9.61 39.27 5.93 12.13 3.43 3.19 2.52 1.51 1.53 0.45 1.07 0.19 0.69 0.07 0.40 0.02         16 17     10.22 43.94 6.30 13.57 3.64 3.57 2.68 1.69 1.62 0.50 1.14 0.21 0.74 0.07 0.43 0.02         17 18     10.82 48.85 6.67 15.09 3.86 3.97 2.83 1.88 1.72 0.56 1.20 0.23 0.78 0.08 0.45 0.02         18 19     11.42 53.99 7.04 16.68 4.07 4.39 2.99 2.07 1.81 0.61 1.27 0.26 0.82 0.09 0.48 0.02         19 20     12.02 59.37 7.42 18.34 4.28 4.83 3.15 2.28 1.91 0.68 1.34 0.28 0.87 0.10 0.50 0.03         20 22     13.22 70.83 8.16 21.88 4.71 5.76 3.46 2.72 2.10 0.81 1.47 0.34 0.95 0.12 0.55 0.03 0.35 0.01     22 24     14.42 83.22 8.90 25.71 5.14 6.77 3.78 3.20 2.29 0.95 1.61 0.40 1.04 0.14 0.60 0.04 0.38 0.01     24 26     15.62 96.51 9.64 29.81 5.57 7.85 4.09 3.71 2.48 1.10 1.74 0.46 1.13 0.16 0.65 0.04 0.42 0.01     26 28         10.38 34.20 6.00 9.00 4.41 4.25 2.67 1.26 1.87 0.53 1.21 0.18 0.70 0.05 0.45 0.02     28 30         11.12 38.86 6.43 10.23 4.72 4.83 2.86 1.43 2.01 0.60 1.30 0.21 0.76 0.06 0.48 0.02 0.33 0.01 30 35         12.98 51.70 7.50 13.61 5.51 6.43 3.34 1.91 2.34 0.80 1.52 0.28 0.88 0.07 0.56 0.02 0.39 0.01 35 40         14.83 66.20 8.57 17.43 6.30 8.23 3.82 2.44 2.68 1.03 1.73 0.36 1.01 0.10 0.64 0.03 0.44 0.01 40 45         16.68 82.34 9.64 21.68 7.08 10.24 4.30 3.04 3.01 1.28 1.95 0.44 1.13 0.12 0.72 0.04 0.50 0.02 45 50         18.54 100.08 10.71 26.35 7.87 12.45 4.77 3.69 3.35 1.55 2.17 0.54 1.26 0.14 0.80 0.05 0.55 0.02 50 55             11.78 31.44 8.66 14.85 5.25 4.40 3.68 1.85 2.38 0.64 1.38 0.17 0.88 0.06 0.61 0.02 55 60             12.85 36.94 9.44 17.45 5.73 5.17 4.02 2.18 2.60 0.76 1.51 0.20 0.96 0.07 0.67 0.03 60 65             13.93 42.84 10.23 20.23 6.21 6.00 4.35 2.53 2.82 0.88 1.64 0.23 1.04 0.08 0.72 0.03 65 70             15.00 49.14 11.02 23.21 6.68 6.88 4.69 2.90 3.03 1.01 1.76 0.27 1.12 0.09 0.78 0.04 70 75             16.07 55.84 11.81 26.37 7.16 7.82 5.02 3.29 3.25 1.14 1.89 0.30 1.20 0.10 0.83 0.04 75 80             17.14 62.93 12.59 29.72 7.64 8.81 5.35 3.71 3.47 1.29 2.01 0.34 1.28 0.11 0.89 0.05 80 85             18.21 70.40 13.38 33.25 8.12 9.86 5.69 4.15 3.68 1.44 2.14 0.38 1.36 0.13 0.94 0.05 85 90             19.28 78.27 14.17 36.97 8.59 10.96 6.02 4.62 3.90 1.60 2.27 0.43 1.44 0.14 1.00 0.06 90 95             20.35 86.51 14.95 40.86 9.07 12.11 6.36 5.10 4.12 1.77 2.39 0.47 1.52 0.16 1.05 0.06 95 100             21.42 95.13 15.74 44.93 9.55 13.32 6.69 5.61 4.33 1.95 2.52 0.52 1.60 0.17 1.11 0.07 100 110                 17.31 53.61 10.50 15.89 7.36 6.69 4.77 2.33 2.77 0.62 1.76 0.21 1.22 0.08 110 120                 18.89 62.98 11.46 18.67 8.03 7.86 5.20 2.73 3.02 0.73 1.92 0.24 1.33 0.10 120 130                 20.46 73.04 12.41 21.65 8.70 9.12 5.63 3.17 3.27 0.84 2.08 0.28 1.44 0.12 130 140                 22.04 83.79 13.37 24.84 9.37 10.46 6.07 3.64 3.52 0.97 2.24 0.32 1.55 0.13 140 150                 23.61 95.21 14.32 28.23 10.04 11.89 6.50 4.13 3.78 1.10 2.40 0.37 1.66 0.15 150 160                     15.28 31.81 10.71 13.40 6.94 4.66 4.03 1.24 2.56 0.41 1.77 0.17 160 170                     16.23 35.59 11.38 14.99 7.37 5.21 4.28 1.39 2.72 0.46 1.89 0.19 170 180                     17.19 39.56 12.05 16.66 7.80 5.79 4.53 1.54 2.88 0.51 2.00 0.21 180 190                     18.14 43.73 12.72 18.42 8.24 6.40 4.78 1.71 3.04 0.57 2.11 0.23 190 200                     19.10 48.09 13.39 20.25 8.67 7.04 5.03 1.88 3.20 0.62 2.22 0.26 200 225                     21.49 59.81 15.06 25.19 9.75 8.75 5.66 2.33 3.60 0.78 2.50 0.32 225 250                         16.73 30.62 10.84 10.64 6.29 2.84 4.00 0.94 2.77 0.39 250 275                         18.41 36.53 11.92 12.69 6.92 3.38 4.40 1.13 3.05 0.46 275 300                         20.08 42.91 13.00 14.91 7.55 3.97 4.81 1.32 3.33 0.54 300 325                         21.75 49.77 14.09 17.30 8.18 4.61 5.21 1.53 3.60 0.63 325 350                             15.17 19.84 8.81 5.29 5.61 1.76 3.88 0.72 350 375                             16.25 22.54 9.44 6.01 6.01 2.00 4.16 0.82 375 400                             17.34 25.41 10.07 6.77 6.41 2.25 4.44 0.92 400 425                             18.42 28.43 10.70 7.58 6.81 2.52 4.71 1.03 425 450                             19.51 31.60 11.33 8.42 7.21 2.80 4.99 1.15 450 475                             20.59 34.93 11.96 9.31 7.61 3.10 5.27 1.27 475 500                             21.67 38.41 12.59 10.24 8.01 3.41 5.55 1.39 500 550                                 13.84 12.21 8.81 4.07 6.10 1.66 550 600                                 15.10 14.35 9.61 4.78 6.66 1.95 600   Shaded Area represents Velocities over 5 FPS. Use with caution.     OD = Outside Diameter;  ID = Inside Diameter; FPS = Feet Per Second;  GPM = Gallons Per Minute C = Smoothness (roughness) coefficient used in Hazen William's Equation     SDR = Standard Dimension Ratio     Velocity FPS calculated using formula:  Friction Losses (PSI) calculated using Hazen William's formula:       These values are calculated using above formula. Values may vary from other published data due to rounding. Values should be used with caution on large systems. Ramesh Kumar, Cal Poly, Pomona.
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